Christine Dudgeon was waist-deep in the seagrass meadows of Milne Bay, Papua New Guinea, past midnight in March 2025, when she saw it—a nearly 70-centimetre shark gliding along the seabed, unlike any she’d studied before. As she shone her torch, the creature froze, revealing a pattern of spots and dashes across its back that looked like Braille or Morse code. In that moment, a new species was glimpsed by science: Hemiscyllium dudgeonae, a walking shark that uses its pectoral fins like legs to waddle across reef flats at low tide—a behavior long known to local communities who call it kadedekedewa, meaning “dog shark” or “lazy shark.”
This discovery isn’t just a taxonomic triumph—it’s a stark reminder of how much remains unknown in one of Earth’s most biodiverse regions. Walking sharks, all nine previously known species of which are confined to northern Australia and New Guinea, are small, bottom-dwelling predators that feed on invertebrates. They’re most easily told apart by their unique skin patterns, and Hemiscyllium dudgeonae stands out dramatically. Its intricate markings, combined with genetic analysis conducted at the University of the Sunshine Coast, confirmed it as a distinct lineage, now named in honor of Dudgeon herself.
Over the following days, the research team—led by Dudgeon and her colleague Jess Blakeway—captured 11 individuals across three sites in Milne Bay. Nine were sampled and released; three were kept for further study. All evidence points to this shark being endemic to this single bay, making it incredibly vulnerable. "This species adds to Papua New Guinea’s extraordinary biodiversity, yet it faces local extinction without urgent conservation action," says Blakeway.
That urgency is driven by mounting threats: coastal development, the expansion of palm oil plantations, and coral bleaching are degrading the delicate reef ecosystems these sharks depend on. With no known populations outside Milne Bay, H. dudgeonae is likely the most endangered of all walking sharks—a creature only just discovered may already be on the brink.
Still, the discovery offers hope. Naming the shark after a leading researcher shines a light on the importance of marine science, while the involvement of local knowledge underscores a deeper truth: communities have been observing and naming nature long before scientists arrive. As conservation discussions unfold, the story of kadedekedewa—its strange gait, its coded skin, its quiet resilience—could become a symbol of why protecting small, overlooked corners of the ocean matters. In a world of loss, a newly found shark reminds us that wonder still swims in the shallows.